This is a request for an independent epidemiological study of brain tumors that constitutes an extension of two similar projects: (a) Grant No. R01-CA-7082-01; Dr. Susan Preston-Martin, University of Southern California at Los Angeles, Principal Investigator. (b) An international study coordinated by the IARC, Lyon. Epidemiologic studies of brain tumors (BT) done to date suggest that long suspected BT risk factors such as ionizing radiation, head trauma and known genetic predispositions account for only a small proportion of incident cases. A compelling experimental model suggests that N-nitroso compounds (NOC) may cause BT in humans. This proposed study, in conjunction with the concurrent US study, will focus on the NOC/BT hypothesis. We propose to study all cases of primary BT diagnosed from 1985-1991 among subjects younger than 15 years of age living in Israel. We expect to interview the biological mothers of 300 children with childhood BT diagnosed during this 7 year period and 600 controls stratified age and sex. The questionnaire asks about sources of NOC exposure such as diet, drugs, cosmetics, rubber products and parental occupational exposures. Pathology slides of all cases will be reviewed by a single pediatric neuropathologist. The proposed study is constructed in part along the lines of the LA study, with Dr. Preston-Martin serving as Co-PI. This will enable eventually a joint analysis of the data, in addition to individual analyses at each study center. Data will also be comparable with data from a concurrent international study.